Final setup. Got my velocity stacks, got my fuel filter, got all the fittings, all the hose, just need to wrap up three final details - electrical power for the pump, a blockoff plate for my mechanical fuel pump, and insulated hose clamps for the long spans.

Because I wasn't doing enough, I ordered Hella E code headlights, too. Got the headlights in, got the relay sub-harness made, got the initial cut at running, then ordered 50F9 idle jets to replace the 45F9 jets in 'em from the builder.

Before I got them, they'd been sitting on a shelf for a while, so I had to coax them back to life, and the needle valve in the middle carb's float chamber was very firmly stuck for some reason. But all that's fixed now, and it runs, except for a flat spot at around 2500 where the carbs should smoothly pass from the progression circuit to the main circuit (it leans out and bogs). But that's what the richer idle jets are for.

Once the mains come in, it's a revelation, and it pulls hard straight to 7000.

I discovered one small issue that I'll need to correct, in that the tank vent line is now kinked, and not letting me fill the gas tank beyond about 2/3rds, but I think I can solve that with one of those anti-collapse springs that set inside hoses (I just hope they make 'em in 5/8").

It always amused me that the Datsun purists who only want Japanese wheels from Enkei or SSR don't bat an eyelash about pulling the trigger on a set of Italian carburetors.

But, now I've got Italian carbs on this one. And the other one's got German wheels and Italian brakes.

The stock radio is AM, powers one speaker (to the tune of 4W), has a weird-ass rocker switch in the dash to raise and lower the antenna, isn't built to any sort of DIN standard, and is super duper expensive. Mine works perfectly, and it's a nice visual piece in the dash, so I wanted to keep it, and keep it working.

So, with that in mind, I set out to make a stealth setup for the car. It will stream bluetooth from the phone, will be on when the radio is off, will add a right speaker in addition to a decent left, and won't be visible externally.

It's kind of a tight set of conditions, and it made for a couple tradeoffs that compromise sound quality a little bit. The biggest tradeoff is that the stock brackets only have room for a 5.25" speaker, and a maximum depth of a little over 2". So, I bought Match MS5x speakers.

I bought a Sure bluetooth module to match up to a small class D amp that I bought from gee, which is a basic 2x50W unit that has a little 12-24V stepup circuit in front of it.

Here's the initial "will it work" board:

I didn't want to modify the radio, because like I said, it's super expensive, but I really needed a radio-switched 12V. So, I looked at the service manual (which included a complete circuit diagram), took a deep breath, and heated up the soldering iron.

I added the blue wire in the picture:

Fortunately, there was a spare output in the bulkhead, so I didn't even have to mod the case.

I repurposed the antenna harness, so that i could get ignition and radio-switched power to the hatch without having to run new wires, which had the added bonus of allowing me to use a modern power antenna.

I bodged up a schematic, that used one more relay than necessary, but I was a little worried about drawing too much through the radio +12V. Two constraints that you don't normally have to deal with that I did are: 1) backfeeding the amp usually doesn't do anything, but it has a history of blowing up the Hitachi radios, so I needed to switch speaker outputs according to which is on. Also, the amp I got doesn't like being on without having a load on the speaker terminals, so when the radio is on, the amp must be off.

Then I started assembling.

Finished:

Right speaker, installed in all the mess of hoses that Nissan decided was necessary to handle slosh and vapor in the fuel tank. This is just a spare left bracket, with the studs pounded out and new screws installed:

Amp in place, in the compartment behind the Driver's seat.

Test! Because the amp is from a Canadian, I had to make its first play Tom Sawyer.

Not shown: making a 26" diameter ring for connecting the top to the glass tub, or making the 12" diameter ring for flush-mounting the sub to the top.

Amp, mounted under the driver's seat. The wire split goes to the other amp, in the behind-the-seat compartment on the driver's side.

Wrapped up, all stealthy. You can't see that it's installed, and the original AM still works fine with the one speaker on the DS of the hatch. The only outward indication that it's working at all is the fact that the antenna switch isn't hooked up to anything anymore. Forgive the handprints, I was excited, and hadn't cleaned up yet.

I balked some years ago at the cost of replacing the stamped metal tray for my battery and instead put a container in for moving it to the hatch. OMGIn doing so, I became subject to a number of rules regarding how the car must be prepared to run on the track, the most onerous of which is a kill switch on "the rear-most part" of the car.

For reference, here's the ever-popular internally regulated 60/70A Hitachi from a 280ZX:

I've had a Moroso 74102 for some time acting as a kill switch (mounted to the rear panel, through the license plate), installed per the directions but I'm getting ready to run a 100A alternator (to support some other modifications), and realized that I'd been dangerously wrong on the install for some time. OMGSee, the 74102 is limited to 20A charging capacity, which runs afoul of even the most modest of 240Z alternators' peak output (I say peak, because certainly they aren't running at their rated output, when the battery is charged). OMGI noticed this when I melted my first 74102 after getting a jump on a dead battery (the 10 gauge wire running back certainly got hot as well).

So, after rethinking my options, I decided to go with the Longacre instructions (below) and use the switch to kill the field wire. OMGThis works fine, if you've got a race car, and you use the kill switch to shut the car down. OMGOtherwise, it'll run the battery dead overnight.

After rethinking my options again, I happened on a simple diagram that helped me out.

Basically, the field wire should only receive ignition switched power. OMGThe problem, then, is figuring out how to get ignition switched power that won't also get fed by the alternator. OMGSo I kept the leg of the Moroso 74102 that their instructions intended for charging the battery, but used it as the source for a relay that is triggered by the ignition switch, like so (though adding the 1N5402 relay to keep the car from running on after the key is turned off):

Now, you can run a (fused) wire from the alternator to the starter post at whatever you think is a safe gauge, which hopefully already has a big 2 gauge cable running to the back (either with its own breaker, or relying on the switch to melt-safe). OMGI went with 4 gauge, and an inline 100A fuse (though not visible):

I'll be switching to a GM 3-wire alternator soon, but this wiring should support the new one just fine.